<template>
    <div id="body" v-show="showModal">
        <main>
            <form @submit="login" class="form">
                <button @click="showModal = false" class="close-btn" type="button">
                    <a-icon type="close-circle"/>
                </button>
                <div class="form__cover"></div>
                <div class="form__loader">
                    <div class="spinner active">
                        <svg class="spinner__circular" viewBox="25 25 50 50">
                            <circle class="spinner__path" cx="50" cy="50" fill="none" r="20" stroke-miterlimit="10"
                                    stroke-width="4"></circle>
                        </svg>
                    </div>
                </div>
                <div class="form__content">
                    <h1>Authorization</h1>
                    <div style="margin-bottom: 25px; text-align: left;">
                        <div class="styled-input">
                            <input autocomplete="off" class="styled-input__input" name="username" type="text"
                                   v-model="username">
                            <div class="styled-input__placeholder"><span
                                    class="styled-input__placeholder-text">Username</span></div>
                            <div class="styled-input__circle"></div>
                        </div>
                        <span class="invalid-message"
                              v-show="usernameValidateCallback">{{usernameValidateCallback}}</span>
                    </div>
                    <div style="margin-bottom: 25px; text-align: left;">
                        <div class="styled-input">
                            <input autocomplete="new-password" class="styled-input__input" name="password"
                                   type="password" v-model="password">
                            <div class="styled-input__placeholder"><span
                                    class="styled-input__placeholder-text">Password</span></div>
                            <div class="styled-input__circle"></div>
                        </div>
                        <span class="invalid-message"
                              v-show="passwordValidateCallback">{{passwordValidateCallback}}</span>
                    </div>
                    <button class="styled-button" type="Submit">
                        <span class="styled-button__real-text-holder" v-if="!loading">
                            <span class="styled-button__real-text">Submit</span>
                            <span class="styled-button__moving-block face">
                                <span class="styled-button__text-holder">
                                    <span class="styled-button__text">Submit</span>
                                </span>
                            </span>
                            <span class="styled-button__moving-block back">
                                <span class="styled-button__text-holder">
                                    <span class="styled-button__text">Submit</span>
                                </span>
                            </span>
                        </span>
                        <a-spin v-else>
                            <a-icon slot="indicator" spin style="color: white;" type="loading"/>
                        </a-spin>
                    </button>
                </div>
            </form>
        </main>
    </div>
</template>

<script>
    import {Icon, Spin} from "ant-design-vue";
    import axios from "axios";

    export default {
        name: "LoginCard",
        components: {
            AIcon: Icon,
            ASpin: Spin
        },
        data() {
            return {
                showModal: false,
                username: '',
                password: '',
                usernameValidateCallback: '',
                passwordValidateCallback: '',
                loading: false
            }
        },
        methods: {
            login: function (e) {
                let vue = this;

                e.preventDefault();

                // Check input validation
                this.usernameValidateCallback = this.username ? '' : '请填写正确的用户名';
                this.passwordValidateCallback = this.password ? '' : '请填写正确的密码';
                if (this.usernameValidateCallback || this.passwordValidateCallback) return;

                vue.loading = true;
                axios.post("/user/login/", {
                    username: this.username,
                    password: this.password
                }).then(function (response) {
                    localStorage.setItem('token', response.data.token);
                    vue.showModal = false;
                    vue.$emit("loginSuccess");
                }).catch(function (error) {
                    if (error.response.status == 400) {
                        vue.usernameValidateCallback = "错误的用户名或密码";
                        vue.passwordValidateCallback = "错误的用户名或密码";
                    }
                }).finally(function () {
                    vue.loading = false;
                })
            }
        },
        watch: {
            // 关闭登录框时清除数据和提示信息
            showModal: function (newVal) {
                if (!newVal) {
                    this.username = '';
                    this.password = '';
                    this.usernameValidateCallback = '';
                    this.passwordValidateCallback = '';
                }
            }
        },
        mounted() {
            'use strict';

            var placeholders = document.querySelectorAll('.styled-input__placeholder-text'),
                inputs = document.querySelectorAll('.styled-input__input');

            placeholders.forEach(function (el) {
                var value = el.innerText,
                    html = '';
                var _iterator = value, _isArray = Array.isArray(_iterator), _i = 0;
                _iterator = _isArray ? _iterator : _iterator[Symbol.iterator]();
                for (; ;) {
                    var _ref;

                    if (_isArray) {
                        if (_i >= _iterator.length) break;
                        _ref = _iterator[_i++];
                    } else {
                        _i = _iterator.next();
                        if (_i.done) break;
                        _ref = _i.value;
                    }

                    var w = _ref;

                    if (!value) value = '&nbsp;';
                    html += '<span class="letter">' + w + '</span>';
                }
                el.innerHTML = html;
            });

            inputs.forEach(function (el) {
                var parent = el.parentNode;
                el.addEventListener('focus', function () {
                    parent.classList.add('filled');
                    placeholderAnimationIn(parent, true);
                }, false);
                el.addEventListener('blur', function () {
                    if (el.value.length) return;
                    parent.classList.remove('filled');
                    placeholderAnimationIn(parent, false);
                }, false);
            });

            function placeholderAnimationIn(parent, action) {
                var act = action ? 'add' : 'remove';
                var letters = parent.querySelectorAll('.letter');
                letters = [].slice.call(letters, 0);
                if (!action) letters = letters.reverse();
                letters.forEach(function (el, i) {
                    setTimeout(function () {
                        var contains = parent.classList.contains('filled');
                        if (action && !contains || !action && contains) return;
                        el.classList[act]('active');
                    }, 50 * i);
                });
            }

            document.getElementById("body").classList.add('on-start');
            document.getElementById("body").classList.add('document-loaded');
        }
    }
</script>

<style scoped>
    @import url('https://fonts.googleapis.com/css?family=Roboto');

    #body {
        all: initial;
        font-family: 'Roboto', sans-serif;
        letter-spacing: 0.02em;
    }

    * {
        box-sizing: border-box;
    }

    main {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        display: -webkit-box;
        display: -ms-flexbox;
        display: flex;
        -webkit-box-pack: center;
        -ms-flex-pack: center;
        justify-content: center;
        -webkit-box-align: center;
        -ms-flex-align: center;
        align-items: center;
        background: #86868670;
        z-index: 999;
    }

    .form {
        display: -webkit-box;
        display: -ms-flexbox;
        display: flex;
        -webkit-box-align: center;
        -ms-flex-align: center;
        align-items: center;
        -webkit-box-pack: center;
        -ms-flex-pack: center;
        justify-content: center;
        position: relative;
        width: 400px;
        height: 400px;
        -ms-flex-negative: 0;
        flex-shrink: 0;
        padding: 20px;
        border-radius: 5px;
    }

    .form__loader {
        display: -webkit-box;
        display: -ms-flexbox;
        display: flex;
        position: absolute;
        left: 0;
        top: 0;
        height: 100%;
        width: 100%;
        -webkit-box-pack: center;
        -ms-flex-pack: center;
        justify-content: center;
        -webkit-box-align: center;
        -ms-flex-align: center;
        align-items: center;
        z-index: -4;
        -webkit-transition: all 0.5s ease;
        transition: all 0.5s ease;
    }

    .form__content {
        text-align: center;
        display: -webkit-box;
        display: -ms-flexbox;
        display: flex;
        -webkit-box-pack: center;
        -ms-flex-pack: center;
        justify-content: center;
        -webkit-box-orient: vertical;
        -webkit-box-direction: normal;
        -ms-flex-direction: column;
        flex-direction: column;
        position: relative;
        opacity: 0;
        -webkit-transform: translateY(10px);
        transform: translateY(10px);
        -webkit-transition: all 0.5s ease 0.7s;
        transition: all 0.5s ease 0.7s;
    }

    .form__cover {
        position: absolute;
        left: 0;
        top: 0;
        height: 100%;
        width: 100%;
        z-index: -4;
        border-radius: 7px;
        overflow: hidden;
        -webkit-transition: all 0.3s ease 0.8s;
        transition: all 0.3s ease 0.8s;
        box-shadow: 0 0 0 0 rgba(0, 0, 0, 0);
    }

    .form__cover:after {
        content: '';
        position: absolute;
        left: 0;
        top: 0;
        height: 100%;
        width: 100%;
        background: #4d317a;
        z-index: -4;
        border-radius: 50%;
        -webkit-transition: all 1.5s ease 0.3s;
        transition: all 1.5s ease 0.3s;
        -webkit-transform: scale(0);
        transform: scale(0);
    }

    .form__cover:before {
        content: '';
        position: absolute;
        left: 0;
        top: 0;
        height: 100%;
        width: 100%;
        background: white;
        z-index: -5;
        border-radius: 50%;
        -webkit-transition: all 0.5s ease;
        transition: all 0.5s ease;
        -webkit-transform: scale(0);
        transform: scale(0);
    }

    #body.on-start .form__cover:before {
        -webkit-transform: scale(0.15);
        transform: scale(0.15);
    }

    #body.document-loaded .form__loader {
        -webkit-transform: scale(0);
        transform: scale(0);
        opacity: 0;
        visibility: hidden;
    }

    #body.document-loaded .form__content {
        opacity: 1;
        -webkit-transform: none;
        transform: none;
    }

    #body.document-loaded .form__cover {
        box-shadow: 0 20px 50px rgba(0, 0, 0, 0.3);
    }

    #body.document-loaded .form__cover:after {
        -webkit-transform: scale(2);
        transform: scale(2);
    }

    #body.document-loaded .form__cover:before {
        -webkit-transition: opacity 0.3s ease 0.8s, -webkit-transform 2s ease;
        transition: opacity 0.3s ease 0.8s, -webkit-transform 2s ease;
        transition: transform 2s ease, opacity 0.3s ease 0.8s;
        transition: transform 2s ease, opacity 0.3s ease 0.8s, -webkit-transform 2s ease;
        -webkit-transform: scale(2);
        transform: scale(2);
        opacity: 0;
    }

    h1 {
        font-size: 40px;
        margin: 15px 0 20px 0;
        letter-spacing: 0.05em;
        color: #714cab;
        font-weight: 700;
    }

    .styled-button {
        -webkit-appearance: none;
        -webkit-user-select: none;
        cursor: pointer;
        font-size: 14px;
        width: 100%;
        height: 50px;
        outline: none;
        background: none;
        position: relative;
        color: #492e72;
        border-radius: 3px;
        margin-bottom: 25px;
        border: none;
        text-transform: uppercase;
        font-weight: 700;
        letter-spacing: 0.1em;
        background: #714cac;
        -webkit-transition: all 0.3s ease;
        transition: all 0.3s ease;
        overflow: hidden;
    }

    .styled-button__real-text-holder {
        position: relative;
    }

    .styled-button__real-text {
        color: transparent;
        display: inline-block;
    }

    .styled-button__text-holder {
        position: absolute;
        left: 0;
        top: 0;
        height: 100%;
        width: 100%;
        display: -webkit-box;
        display: -ms-flexbox;
        display: flex;
        -webkit-box-align: center;
        -ms-flex-align: center;
        align-items: center;
        -webkit-box-pack: center;
        -ms-flex-pack: center;
        justify-content: center;
        -webkit-transition: all 0.3s ease;
        transition: all 0.3s ease;
    }

    .styled-button__moving-block {
        -webkit-transition: all 0.3s ease;
        transition: all 0.3s ease;
        position: absolute;
        left: 0;
        top: 0;
        height: 100%;
        width: 100%;
        overflow: hidden;
    }

    .styled-button__moving-block.back {
        color: white;
        -webkit-transform: translateX(-100%);
        transform: translateX(-100%);
    }

    .styled-button__moving-block.back .styled-button__text-holder {
        -webkit-transform: translateX(100%);
        transform: translateX(100%);
    }

    .styled-button:hover,
    .styled-button:active {
        box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
        background: #7a51bb;
    }

    .styled-button:hover .face,
    .styled-button:active .face {
        -webkit-transform: translateX(100%);
        transform: translateX(100%);
    }

    .styled-button:hover .face .styled-button__text-holder,
    .styled-button:active .face .styled-button__text-holder {
        -webkit-transform: translateX(-100%);
        transform: translateX(-100%);
    }

    .styled-button:hover .back,
    .styled-button:active .back {
        -webkit-transform: translateX(0);
        transform: translateX(0);
    }

    .styled-button:hover .back .styled-button__text-holder,
    .styled-button:active .back .styled-button__text-holder {
        -webkit-transform: translateX(0);
        transform: translateX(0);
    }

    .styled-button:active {
        box-shadow: 0 0 5px rgba(0, 0, 0, 0.3);
    }

    .styled-input {
        width: 100%;
        position: relative;
        border: 1px solid rgba(255, 255, 255, 0.2);
        border-radius: 3px;
        -webkit-transition: all 0.3s ease;
        transition: all 0.3s ease;
    }

    .styled-input__circle {
        position: absolute;
        left: 0;
        top: 0;
        width: 100%;
        height: 100%;
        z-index: -2;
        overflow: hidden;
        border-radius: 3px;
    }

    .styled-input__circle:after {
        content: '';
        position: absolute;
        left: 16.5px;
        top: 19px;
        height: 14px;
        width: 14px;
        z-index: -2;
        border-radius: 50%;
        background: rgba(255, 255, 255, 0.15);
        box-shadow: 0 0 10px rgba(255, 255, 255, 0);
        -webkit-transition: opacity 1s ease, -webkit-transform 0.6s ease;
        transition: opacity 1s ease, -webkit-transform 0.6s ease;
        transition: transform 0.6s ease, opacity 1s ease;
        transition: transform 0.6s ease, opacity 1s ease, -webkit-transform 0.6s ease;
    }

    .styled-input__input {
        width: 100%;
        -webkit-appearance: none;
        font-size: 14px;
        outline: none;
        background: none;
        padding: 18px 15px;
        color: #ceafff;
        border: none;
        font-weight: 600;
        letter-spacing: 0.035em;
    }

    .styled-input__placeholder {
        position: absolute;
        left: 0;
        top: 0;
        width: 100%;
        height: 100%;
        display: -webkit-box;
        display: -ms-flexbox;
        display: flex;
        -webkit-box-align: center;
        -ms-flex-align: center;
        align-items: center;
        z-index: -1;
        padding-left: 45px;
        color: white;
    }

    .styled-input__placeholder-text {
        -webkit-perspective: 500px;
        perspective: 500px;
        display: inline-block;
    }

    .styled-input__placeholder-text >>> .letter {
        display: inline-block;
        vertical-align: middle;
        position: relative;
        -webkit-animation: letterAnimOut 0.25s ease forwards;
        animation: letterAnimOut 0.25s ease forwards;
        text-shadow: 0 0 5px;
    }

    .styled-input__placeholder-text >>> .letter.active {
        -webkit-animation: letterAnimIn 0.25s ease forwards;
        animation: letterAnimIn 0.25s ease forwards;
    }

    .styled-input:hover {
        border-color: rgba(255, 255, 255, 0.4);
    }

    .styled-input.filled {
        border-color: rgba(255, 255, 255, 0.2);
    }

    .styled-input.filled .styled-input__circle:after {
        -webkit-transform: scale(37);
        transform: scale(37);
        opacity: 0;
    }

    @-webkit-keyframes letterAnimIn {
        0% {
            -webkit-transform: translate(0, 0);
            transform: translate(0, 0);
        }
        25% {
            -webkit-transform: translate(0, 10px);
            transform: translate(0, 10px);
            color: red;
        }
        45% {
            -webkit-transform: translate(0, 10px);
            transform: translate(0, 10px);
            opacity: 0;
            color: red;
        }
        55% {
            -webkit-transform: translate(0, 10px);
            transform: translate(0, 10px);
            opacity: 0;
        }
        56% {
            -webkit-transform: translate(-30px, -27px);
            transform: translate(-30px, -27px);
            opacity: 0;
            color: #00ff6b;
        }
        76% {
            color: #00ff6b;
            opacity: 1;
            -webkit-transform: translate(-30px, -27px);
            transform: translate(-30px, -27px);
        }
        100% {
            -webkit-transform: translate(-30px, -27px);
            transform: translate(-30px, -27px);
            opacity: 1;
        }
    }

    @keyframes letterAnimIn {
        0% {
            -webkit-transform: translate(0, 0);
            transform: translate(0, 0);
        }
        25% {
            -webkit-transform: translate(0, 10px);
            transform: translate(0, 10px);
            color: red;
        }
        45% {
            -webkit-transform: translate(0, 10px);
            transform: translate(0, 10px);
            opacity: 0;
            color: red;
        }
        55% {
            -webkit-transform: translate(0, 10px);
            transform: translate(0, 10px);
            opacity: 0;
        }
        56% {
            -webkit-transform: translate(-30px, -27px);
            transform: translate(-30px, -27px);
            opacity: 0;
            color: #00ff6b;
        }
        76% {
            color: #00ff6b;
            opacity: 1;
            -webkit-transform: translate(-30px, -27px);
            transform: translate(-30px, -27px);
        }
        100% {
            -webkit-transform: translate(-30px, -27px);
            transform: translate(-30px, -27px);
            opacity: 1;
        }
    }

    @-webkit-keyframes letterAnimOut {
        0% {
            -webkit-transform: translate(-30px, -27px);
            transform: translate(-30px, -27px);
            opacity: 1;
        }
        25% {
            -webkit-transform: translate(-30px, -40px);
            transform: translate(-30px, -40px);
            opacity: 0;
        }
        45% {
            -webkit-transform: translate(0, 10px);
            transform: translate(0, 10px);
            opacity: 0;
        }
        55% {
            -webkit-transform: translate(0, 10px);
            transform: translate(0, 10px);
            opacity: 0;
            color: red;
        }
        56% {
            -webkit-transform: translate(0, 10px);
            transform: translate(0, 10px);
            color: red;
        }
        100% {
            -webkit-transform: translate(0, 0);
            transform: translate(0, 0);
        }
    }

    @keyframes letterAnimOut {
        0% {
            -webkit-transform: translate(-30px, -27px);
            transform: translate(-30px, -27px);
            opacity: 1;
        }
        25% {
            -webkit-transform: translate(-30px, -40px);
            transform: translate(-30px, -40px);
            opacity: 0;
        }
        45% {
            -webkit-transform: translate(0, 10px);
            transform: translate(0, 10px);
            opacity: 0;
        }
        55% {
            -webkit-transform: translate(0, 10px);
            transform: translate(0, 10px);
            opacity: 0;
            color: red;
        }
        56% {
            -webkit-transform: translate(0, 10px);
            transform: translate(0, 10px);
            color: red;
        }
        100% {
            -webkit-transform: translate(0, 0);
            transform: translate(0, 0);
        }
    }

    .spinner {
        position: relative;
        margin: auto;
        width: 50px;
        height: 50px;
        -webkit-transition: all 0.2s ease 0s;
        transition: all 0.2s ease 0s;
    }

    .spinner__circular {
        -webkit-animation: rotate 1.5s linear infinite;
        animation: rotate 1.5s linear infinite;
        -webkit-animation-play-state: paused;
        animation-play-state: paused;
        -webkit-transform-origin: center center;
        transform-origin: center center;
        position: absolute;
        width: 100%;
        height: 100%;
        top: 0;
        left: 0;
        margin: auto;
    }

    .spinner__path {
        stroke-dasharray: 1, 200;
        stroke-dashoffset: 0;
        -webkit-animation: dash 1.3s ease forwards 0.5s;
        animation: dash 1.3s ease forwards 0.5s;
        opacity: 0;
        stroke-linecap: round;
        stroke: #7b23ff;
        -webkit-animation-play-state: running;
        animation-play-state: running;
    }

    @-webkit-keyframes dash {
        0% {
            stroke-dasharray: 1, 200;
            stroke-dashoffset: 0;
            opacity: 0;
        }
        50% {
            stroke-dasharray: 40, 200;
            opacity: 1;
        }
        100% {
            stroke-dasharray: 125, 200;
            opacity: 1;
        }
    }

    @keyframes dash {
        0% {
            stroke-dasharray: 1, 200;
            stroke-dashoffset: 0;
            opacity: 0;
        }
        50% {
            stroke-dasharray: 40, 200;
            opacity: 1;
        }
        100% {
            stroke-dasharray: 125, 200;
            opacity: 1;
        }
    }

    .close-btn {
        position: absolute;
        top: 10px;
        right: 10px;
        font-size: 30px;
        background: none;
        border: 0;
        color: #ffffff94;
        cursor: pointer;
    }

    .close-btn:focus {
        outline: none;
    }

    .invalid-message {
        color: red;
        font-size: 12px;
    }
</style>